Semiconductor device

ABSTRACT

A method for manufacturing a semiconductor device, includes: a step of etching a Si ( 111 ) substrate along a ( 111 ) plane of the Si ( 111 ) substrate to separate a Si ( 111 ) thin-film device having a separated surface along the ( 111 ) plane.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuing application of application Ser. No.12/730,826, filed on Mar. 24, 2010, which is based upon and claims thebenefit of priority from the prior Japanese Patent Application No.2009-084099, filed on Mar. 31, 2009, the entire contents of which isincorporated herein by reference.

BACKGROUND OF INVENTION

1. Field of the Invention

The invention relates to a method for manufacturing a semiconductordevice, a semiconductor device, and a semiconductor composite device,which make it possible, by a low-cost simple process, to obtain a highquality circuit/device forming region having a flat separated surfacefrom a Si substrate.

2. Description of Related Art

Conventionally, a SOI (Silicon on Insulator) substrate has beenmanufactured by: implanting hydrogen ions in a depth direction from asurface of a first single crystal Si substrate to form a hydrogen ionimplanted layer (hydrogen added layer) at a predetermined depth; bondingthe surface of the first single crystal Si substrate to a second singlecrystal Si substrate having an SiO₂ layer; and then separating at a parton the Si substrate side of the hydrogen added layer in the first singlecrystal Si substrate.

In addition, for example, regarding a method for transferring a singlecrystal Si thin-film device layer, a technique using the method forseparation at a hydrogen added layer is disclosed in Japanese PatentApplication Publication No. 2005-26472 (hereinafter referred to asPatent Document 1). The technique disclosed in Patent Document 1 is atechnique in which: a hydrogen ion implanted layer is formed at apredetermined depth in a depth direction from a surface of a singlecrystal Si substrate (first substrate) with a single crystal Sithin-film device formed thereon; the single crystal Si thin-film deviceforming the surface of the single crystal Si substrate (first substrate)is bonded to a surface of an insulating substrate (second substrate);and then the single crystal Si substrate (first substrate) is separatedat the hydrogen added layer in which hydrogen ions are implanted.

SUMMARY OF THE INVENTION

However, in the method for separating the single crystal Si substrate ofPatent Document 1, the implantation of hydrogen ions may cause a defectin the single crystal Si thin-film device layer which is formed on thesingle crystal Si substrate. In addition, the separated surfaceresulting from separation at the hydrogen added layer is badly damagedand is markedly uneven due to the implantation of the hydrogen ions. Forthese reasons, the method requires the additional steps of removing thedamaged surface as well as smoothing the remarkably uneven separatedsurface. Moreover, the method has a problem in the manufacturingprocess, that is, the strict bonding conditions, such as the requirementof a heavier load for bonding and the requirement of a high temperaturefor bonding, in order to bond thick substrates to each other.

Furthermore, this method also has a problem of reliability.Specifically, after the single crystal Si thin film is formed, hydrogenions for the separation are implanted, and high temperature processingis performed, which is required for the step of bonding the substratesto each other. This causes deterioration of the device characteristics.Furthermore, this method has a problem of manufacturing cost.Specifically, adding manufacturing steps including hydrogen ionimplantation and wafer bonding under strict conditions leads to highermanufacturing costs.

A first aspect of the invention is a method for manufacturing asemiconductor device, including: etching a Si (111) substrate along a(111) plane of the Si (111) substrate to separate a Si (111) thin-filmdevice having a separated surface along the (111) plane.

A second aspect of the invention is a semiconductor device including: asubstrate having a surface; and a single crystal Si (111) thin-filmdevice having a first surface forming a circuit/device forming regionand a second surface opposed to the first surface. The second surface ofthe single crystal Si (111) thin-film device is directly contacted withand thus fixed on the surface of the substrate.

A third aspect of the invention is a semiconductor composite deviceincluding: a substrate having a surface; a single crystal Si (111)thin-film device having a first surface including a circuit/deviceforming region and a second surface opposed to the first surface; asingle crystal thin-film light emitting device having an electrodeforming surface and a bonding surface provided on an opposite side tothe electrode forming surface. The second surface of the single crystalSi (111) thin-film device is directly contacted with and is thus fixedon the surface of the substrate. The bonding surface of the singlecrystal thin-film light emitting device is directly and closelycontacted with, and is fixed on, the surface of the substrate. Thesingle crystal Si (111) thin-film device and the single crystalthin-film light emitting device are connected by metal wiring.

According to the aspects of the invention, a high quality circuit/deviceforming region having a flat separated surface can be obtained from theSi substrate.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A and FIG. 1B are perspective views illustrating a first substrateconfiguration and a step of manufacturing isolated islands in a firstembodiment of the invention.

FIG. 2A to FIG. 2C are views illustrating manufacturing steps in thefirst embodiment of forming a coating layer and separating a singlecrystal Si (111) thin-film device from the first substrate.

FIG. 3A and FIG. 3B are perspective views illustrating a manufacturingstep of bonding by directly contacting the single crystal Si (111)thin-film device in the first embodiment with a bonding layer forming asurface of a second substrate.

FIG. 4 is a perspective view illustrating a manufacturing step ofattaching electrode wires or the like to the bonding layer of thesurface of the second substrate, to a circuit/device forming region ofthe single crystal Si (111) thin-film device bonded in the firstembodiment.

FIG. 5 is a flowchart of the main manufacturing steps illustrating amethod for manufacturing a semiconductor device of the first embodiment.

FIG. 6A is a plan view of a semiconductor composite chip in a secondembodiment of the invention.

FIG. 6B is a cross sectional view of the semiconductor composite chip inthe second embodiment.

FIG. 7 is a plan view of a one-dimensional light emitting device arraylight source using a semiconductor composite chip according to a thirdembodiment of the invention.

FIG. 8 is a cross sectional view of a LED print head in which theone-dimensional light emitting device array light source in the thirdembodiment is incorporated.

FIG. 9A and FIG. 9B are views illustrating a modification of theone-dimensional light emitting device array light source in the thirdembodiment.

FIG. 10 is a plan view of a 3-terminal light emitting devicetwo-dimensional array and two SI (111) thin-film integrated devices in afourth embodiment.

FIG. 11 is a cross section along the line A-A in FIG. 10 in the fourthembodiment.

FIG. 12 is a cross section along the line B-B in FIG. 10 in the fourthembodiment.

FIG. 13 is a cross section along the line C-C in FIG. 10 in the fourthembodiment.

FIG. 14 is a plan view of a modification of the fourth embodiment.

DETAILED DESCRIPTION OF EMBODIMENTS

Concerning the semiconductor device, the semiconductor composite device,and the method for manufacturing the semiconductor device, first tofourth embodiments of the invention are described with reference to FIG.1 to FIG. 14.

First Embodiment

A first embodiment of the invention is described with reference to FIG.1 to FIG. 5.

FIG. 1A is a perspective view showing a configuration of Si (111)substrate 101, which is a first substrate, and circuit/device formingregion 102 on the surface of Si (111) substrate 101. FIG. 1B is aperspective view showing a step of forming isolated islands 110 byforming an isolation region 120 in a depth direction from the surface ofSi (111) substrate 101 of the first substrate. Each of the isolatedislands 110 includes isolated circuit/device forming region 102 a andisolated substrate region 101 a which are part of Si (111) substrate 101of the first substrate.

In FIG. 1A, circuit/device forming region 102 is a region in which anintegrated circuit including junctions, capacitors, resistors and thelike, and a circuit/device such as a single device, a composite devicesor the like is formed in Si (111) substrate 101 of the first substrate.The thickness of circuit/device forming region 102 depends on thecircuit or device being formed. For example, an integrated circuit usinga CMOS transistor has a thickness of about 10 μm. Herein, the thicknessof circuit/device forming region 102 represents a thickness including athickness which forms a circuit/device and a thickness necessary for thecircuit or device to effectively perform predetermined characteristics.

A crystal plane in the principal surface of the surface of Si (111)substrate 101 is oriented in the (111) plane as indicated by the Millerindex. There is included a case in which the crystal orientation of theprincipal surface of the Si substrate is inclined from the strict (111)plane (hereinafter referred to as a (111) just plane).

As shown in FIG. 1B, isolated islands 110 are formed to have apredetermined size (region) by etching and isolating parts of Si (111)substrate 101 of the first substrate where predetermined circuits,devices and the like are formed in the predetermined sizes. Whenisolated islands 110 are formed, etching is used to form isolatedislands 110 each having a depth including at least circuit/deviceforming region 102 a and isolated substrate region 101 a. For theetching of isolation region 120 for forming each of isolated islands110, any method of dry etching and wet etching or a combination thereofcan be used, depending on the width of isolation region 120 or thedesired shape of the side of isolated island 110. Herein, in a regionother than isolated island 110 of Si (111) substrate 101 of the firstsubstrate having the (111) plane, a surface thereof after etchingisolation region 120 is exposed.

Next, a step of separating isolated island 110 from Si (111) substrate101 of the first substrate is described with reference to FIG. 2A toFIG. 2C, isolated island 110 including isolated circuit/device region102 a and isolated substrate region 101 a. First, as shown in FIG. 2Aand FIG. 2B, coating layer 210 that coats at least a part or all of theside surfaces of isolated island 110 is formed. In FIG. 2A and FIG. 2B,coating layer 210 coats all of the side surfaces of isolated island 110,and partially coats a region of the bottom of isolation region 120.However, this configuration is just an example, and an opening may beformed in part of the side surfaces of isolation region 120 or anopening may be provided on part of coating layer 210. Furthermore, it isalso possible to form coating layer 210 only on in part or all of theside surfaces of isolated island 110. Additionally, a configuration ofcoating layer 210 can be changed, as appropriate, depending on thedesign.

Coating layer 210 can be formed of an insulating film. It is preferablethat coating layer 210 is sufficiently resistant to an etchant foretching Si (111) substrate 101 of the first substrate in order toseparate isolated island 110, to be described later, from Si (111)substrate 101 of the first substrate. Coating layer 210 may be made ofone or more types of material selected from SiN film, SiO₂ film, SiONfilm, Al₂O₃ film, AIN film, PSG film, and BSG film. The film can beformed by selecting a film formation method such as a P-CVD method, aCVD method, a sputtering method or the like, as appropriate. Inaddition, the film may be formed by an application method such as a spinon glass (SOG) or the like or other printing method. Furthermore,coating layer 210 may contain a film made of an organic material inaddition to an inorganic material. When coating layer 210 contains anorganic material film, the surface thereof can be further coated withthe inorganic insulating film material so that coating layer 210 can beresistant to the etchant for Si (111) substrate 101 of the firstsubstrate to be described later.

The point of this embodiment is that Si (111) substrate 101 of the firstsubstrate having isolated island 110 coated with coating layer 210 isselectively etched in a lateral direction of the substrate along the(111) plane in a lower region of isolated island 110 or a regionincluding a part of substrate region 101 a of isolated island 110. Inaddition, prior to the step of soaking the Si (111) substrate of thefirst substrate in the etchant, a first support of isolated island 110and a second support connecting each isolated island 110 or the like canbe provided.

Herein, selective etching in a lateral direction of the substrate alongthe (111) plane means that the etchant etches the Si substrate in adirection perpendicular to the (111) plane at a lower etching rate thanin the lateral direction along the (111) plane. Strictly speaking,etching in the direction perpendicular to the (111) plane (etching in avertical direction) also proceeds together as etching progresses alongthe (111) plane (progress of etching in a horizontal direction),although the etching rate in the vertical direction is lower than theetching rate in the lateral direction. Accordingly, the thickness of asingle crystal Si (111) thin film, separated shown in FIG. 2C, isthinner than that of isolated island 110 of FIG. 1B by a thicknessreduced by etching of a part of substrate region 101 a (partial thinlayer) of isolated island 110 shown in FIG. 2B.

Therefore, for the etchant, it is preferable to use an anisotropicetchant capable of selective etching in a lateral direction of thesubstrate along the Si (111) plane. Herein, anisotropy of etching of theSi (111) substrate of the first substrate means etching in which theetching rate differs depending on the orientation of a crystal face ofSi. In the embodiment, as an anisotropic etchant of Si, an etchantcontaining a chemical selected from KOH ortetra-methyl-ammonium-hydroxide (TMAH) is preferable. In addition,although not preferable, ethylene diamine pyrocatechol (EDP) can be usedas the anisotropic etchant for Si.

In the embodiment, isolated island 110, on which coating layer 210 isprovided, is separated from Si (111) substrate 101 of the firstsubstrate by the anisotropic etching along the Si (111) plane. Isolatedisland 110, including circuit/device forming region 102 a separated fromthe Si (111) substrate 101 or part of substrate region 101 a of isolatedisland 110 by etching, is obtained as a semiconductor thin film. Thissemiconductor thin film is referred to as single crystal Si (111)thin-film device 112. FIG. 2C is a perspective view schematicallyshowing single crystal Si (111) thin-film device 112 which is separatedfrom Si (111) substrate 101. Note that single crystal Si (111) thin-filmdevice 112 comprises circuit/device forming region 102 a and part 101 bremaining after lateral etching along the (111) plane of a lower regionof a separation region for separating isolated island 110 from Si (111)substrate 101 or a region including part of substrate region 101 a ofisolated island 110. Circuit/device forming region 102 a of singlecrystal Si (111) thin-film device 112 includes an inter-layer insulatingfilm or a single layer or multilayer wiring region including metalthin-film wiring, in addition to the single crystal Si (111) region.

The inventor demonstrated for the first time that superior flatness canbe obtained on separated surface A of single crystal Si (111) thin-filmdevice (single crystal Si (111) thin film) 112 by anisotropic etchingalong the Si (111) plane and thus separating isolated island 110.Although not shown in the figures, description is provided of ameasurement result, which was obtained by inter-atom force microscopy(AFM), of flatness of separated surface A of single crystal Si (111)thin-film device 112 separated from Si (111) substrate 101 of the firstsubstrate. Separated surface A of single crystal Si (111) thin-filmdevice 112 separated from Si (111) substrate 101 of the first substratehas flatness in the order of a nanometer, and it is confirmed thatflatness (level difference between a peak and a valley (peak-to-valleyroughness)) of separated surface A (bonding surface) of single crystalSi (111) thin-film device 112 measured in an area of 5 μm² is extremelyfavorable, that is, R_(PV)≦0.2 nm regarding the level difference inshort range unevenness and R_(PV)≦1.6 nm regarding the level differencein long range unevenness (unevenness inclination, 1.56 nm/768 nm≈1/500). It is also confirmed that the flatness is approximatelyequivalent at different measurement positions on separated surface A.Herein short range unevenness means unevenness for example, in the rangeof 100 nm or less. Long range unevenness means unevenness in a range,for example, of 0.5 μm to 1 μm or higher.

Separated surface A improved flatness compared to the separated surfaceof a GaAs based semiconductor thin film obtained by selectively etchinga sacrificing layer experimentally evaluated by the inventor.Specifically, in the structure of the GaAs layer/sacrificing layer/GaAssubstrate fabricated by an MOCVD method, an isolated island of the GaAslayer is formed in such a manner that the sacrificing layer is exposed.Then, the sacrificing layer is selectively and chemically etched toseparate the GaAs layer from the GaAs substrate. The flatness of theseparated surface of the GaAs layer is measured in an area of 5 μm² withthe AFM. Although not shown, the level difference in short rangeunevenness (R_(PV)) is R_(PV)≦1.4 nm. Irrespective of the measurementposition, approximately equivalent flatness is observed within theseparated surface plane.

It is also confirmed that separated surface A that the inventorexperimentally compared has improved flatness, even in comparison to theflatness of a separated surface of a Si layer (Si isolated island) whichis separated by etching an SiO₂ layer, of an SOI substrate, as asacrificing layer. Although not shown, a measurement result obtained bythe inventor is described. Specifically, an SiO₂ layer of an SOIsubstrate (the substrate is an Si (100) substrate, and an Si layer onthe SiO₂ layer is an Si (100) layer) is selectively etched using ahydrofluoric acid based etchant so that the Si (100) layer is separatedfrom the Si (100) substrate. Then, the flatness of the separated surfaceof the Si (100) layer was measured with the AFM in an area of 5 μm². Thelevel difference of the short range unevenness, R_(PV), is 2.3 to 3 nm.Results of measurements at multiple points in the separated surfaceplane show that RPV varies and the structure of unevenness also varies.Thus, variation in R_(PV) unevenness in the separated surface plane isobserved. Since flatness (unevenness) of the separated surface of the Silayer separated from the SOI substrate varies depending on themeasurement position, that is, unevenness of the surface observed usingthe AFM widely varies in the separated surface plane, it can be saidthat the state of the SiO₂/Si substrate interface in the SOI substratevaries, compared with the homogeneity (crystal homogeneity) in thesingle crystal Si substrate.

The results of experiments by the inventor are now described. In anexperiment in which the separated GaAs layer and the Si (100) layer areto be in direct close-contact and bonded to a bonding layer provided onthe substrate at room temperature without using an adhesive, a separatedsurface of the GaAs layer (flatness of the separated surface: R_(PV)≈1.4nm) is able to be directly contacted, bonded to, and fixed on thebonding layer. However, the separated surface of the Si (100) layerhaving an uneven structure, for example, flatness R_(PV) being 2.3 to 3nm, was not able to be in favorable direct close-contact with thebonding layer and was thus not able to be directly bonded to and fixedon the bonding layer. This is because the unevenness of the bondingsurface of the Si thin film separated from the SOI substrate is as highas R_(PV)≈2.3 nm to 3 nm and the flatness of the bonding surface variesin the bonding surface plane.

As described above, the inventor experimentally verified the followingfor the first time. In the experiment, the separated surface of thesingle crystal Si (111) thin film according to the embodiment achievedextremely excellent flatness, compared with the flatness of theseparated surface of the GaAs layer separated from the GaAs substrate byetching a sacrificing layer and the flatness of the separated surface ofthe Si (100) layer separated from the Si (100) substrate by etching theSiO₂ layer of the SOI substrate as a sacrificing layer. Consequently,direct close-contact bonded state was achieved, which could not beachieved using the separated surface of the Si layer separated from theSOI substrate as a bonding surface.

Additionally, when the separated surface of the single crystal Si thinfilm, which is separated from the SOI substrate by etching the SiO₂layer, is polished by CMP, the separated surface of the single crystalSi thin film cannot be flattened by CMP. This is because the singlecrystal Si thin film is thin and thus cannot be firmly supported so asto withstand CMP, so that a crack or defect occurs in the single crystalSi thin film.

When a semiconductor layer separated from a base material substrate isto be placed in direct and close contacted and bonded to a differentsubstrate or on a bonding layer provided on a different substrate, theflatness of the bonding surface of the semiconductor layer is critical.A conceivable methods of bonding the semiconductor layer separated fromthe base material substrate to a heterogeneous substrate or to a bondinglayer provided on the heterogeneous substrate, by directly and closelycontacting the surface to be bonded without using an adhesive, is to useinter-molecular forces between the surfaces to be bonded(inter-molecular force bonding) or to form a strong binding such ascovalent binding at the bonding interface, or the like.

In particular, in a binding method such as the inter-molecular bondingmethod or the covalent binding, it is possible to ease the bondingconditions by placing the surfaces to be bonded in as close proximity aspossible. Easing the bonding conditions means that loads or temperaturesnecessary for bonding can be reduced, i.e., a wide range of conditionsnecessary for favorable bonding can be achieved. Thus, achieving aseparated surface having extremely high flatness can be very beneficialto achieving bonding to a heterogeneous substrate under easier bondingconditions.

In addition, in bonding a single crystal Si (111) thin-film device ofthe embodiment, an extremely flat separated surface is directly bondedto a high thermal conductive substrate or to a high thermal conductivebonding layer on a high thermal conductive substrate. Thus, adhesion ofthe bonding surfaces is excellent, heat resistance in the bondedinterface or the bonding layer can be reduced, and high radiation of thesingle crystal Si (111) thin-film device is achieved.

In the embodiment an anisotropic etchant is used in etching the Si (111)substrate of the first substrate. That is to say, in the etching,etching rate in a depth direction perpendicular to the Si (111) plane islow and etching rate in a direction parallel to the Si (111) plane ishigh. In other words, the characteristic that is used is the fact thatthe etching rate in the direction parallel to the Si (111) plane alongthe bottom face of isolated island 110 is high. Thus, the thickness ofSi (111) substrate 101 of the first substrate after isolated island 110is etched and separated, depends on the size of isolated island 110 tobe separated (the size of an area which is to be etched and lies underthe bottom face of isolated island 110). For example, a change inthickness of Si (111) substrate 100 of the first substrate involved inthe anisotropic etching for separating isolated island 110, 100 μmsquare, is 3 μm to 4 μm. Thus, there is a small change in thickness ofthe Si (111) substrate of the first substrate in the separating step ofisolated island 110. Accordingly, the object of the first embodiment ofthe invention achieved by the anisotropic etching in the directionparallel to the Si (111) plane.

With reference to FIG. 3A and FIG. 3B, described is a step of bondingsingle crystal Si (111) thin-film device 112 to a surface of secondsubstrate 301 of single crystal Si (111) thin-film device 112 obtainedas a result of separation of isolated island 110. As shown in FIGS. 3Aand 3B, bonding layer 310 may coat second substrate 301.

Characteristics of bonding layer 310 on the surface of second substrate301 are, for example, uniformity of the bonding interface with smallvariation, adhesion with no voids, firm bonding strength, or the like.Bonding layer 310 is, for example, an insulating film material layersuch as SiN, SiON, SiO₂, Al₂O₃, AIN or the like; an oxide material layeror a transparent conductive material layer such as ITO, ZnO or the like;an organic material layer such as polyimide, BCB or the like; an organicconductive material layer; a metal layer, an alloy layer, a metalcomposite layer (laminated metal layers) which is selected from Au, Ge,Ni, Ti, Pt, Cu; or the like.

In addition, second substrate 301 is a compound semiconductor substratesuch as a Si substrate, a GaAs substrate, a GaP substrate, an InPsubstrate or the like; a nitride semiconductor substrate such as a GaNsubstrate, an AIN substrate, an AI_(x)Ga_(1-x)N substrate (1≧x≧0), anIn_(x)Ga_(1-x)N substrate (1≧x≧0), an Al_(x)In_(1-x)N substrate (1≧x≧0)or the like; a glass substrate; a quartz substrate; a ceramics substratesuch as AIN or PBN or the like; sapphire substrate; an oxide substratesuch as Linb₃, MgO, GaO₃ or the like; a plastic substrate such as PET,PEN or the like; a metal substrate such as stainless, nickel, copper,brass, aluminum or the like; a plated metal substrate obtained byplating a metal substrate with nickel or copper; a diamond substrate; adiamond-like carbon substrate; or the like. In addition, althoughbonding layer 310 is provided as shown in FIG. 3, a configuration inwhich single crystal Si (111) thin-film device 112 is directly bonded tothe surface of second substrate 301 without providing bonding layer 310is also an option.

In the bonding step, in addition to using intermolecular forces to bedescribed later, it is preferable to use a bonding form in which bindingsuch as covalent binding between bonding interfaces is achieved. Sincethe typical thickness of a single crystal Si (111) thin film is as thinas 10 μm or less, adhesion of the film using an adhesive involves riskof a defect, reliability deterioration, and the like. However, from thestandpoint of fixing the single crystal Si (111) thin film on adifferent substrate, adhesion using an adhesive is also an option.

As shown in FIG. 3A, after cleaning and activation treatment ofseparated surface A of single crystal Si (111) thin-film device 112 andthe surface of bonding layer 310, separated surface A of single crystalSi (111) thin-film device 112 is pressed in close contact with thesurface of bonding layer 310 at room temperature. Thereby, separatedsurface A of single crystal Si (111) thin-film device 112 is bonded tothe surface of bonding layer 310 formed on the surface of secondsubstrate 301 of the different substrate (see the arrow B (bonding step)in FIG. 3A). Consequently, both are bonded (FIG. 3B).

A heating step can be added to the close contact pressing step,depending on the characteristics of the material to be bonded. Asdescribed above, separated surface A of single crystal Si (111)thin-film device 112 is an extremely flat separated surface withR_(PV)≦0.5 nm. Thus, surfaces to be bonded can be placed in proximity inthe order of a nanometer, thereby making it possible to increase theintermolecular forces acting between the bonding surfaces. Hence, in thebonding step, with the intermolecular forces acting between the bondingsurfaces, strong bonding can be achieved. As the flatness of theseparated surface of single crystal Si (111) thin film 112 is extremelyfavorable, in the step of directly attaching and fixing the separatedsurface of single crystal Si (111) thin film 112 to the bonding layer,there is no need to heat the separated surface to a high temperature andfavorable bonding is possible at low temperature such as less than 200°C. or even at room temperature.

Next, as needed, removal of the support and coating layer 210 or thelike is executed. Then, as shown in FIG. 4, fabrication process to makethe devices functional on single crystal Si (111) thin-film device 112and on bonding layer 310 formed on second substrate 301. Bonding layer310 may be provided on a wide area of substrate 301, and additionaldesign changes may be allowed as appropriate. For example, bonding layer310 is provided only on the lower part or near bonded single crystal Si(111) thin-film device 112, and the like. The fabrication process tomake the devices functional means a fabrication process oncircuit/device forming region 102 a, that is to say, formation of aninterlayer insulating film, electrodes, wirings, connection pads (352,354, 356 in FIG. 4), or the like.

FIG. 4 is a perspective view of the embodiment in which single crystalSi (111) thin-film device 112, separated from Si (111) substrate 101 ofthe first substrate, is bonded to the surface of bonding layer 310formed on the surface of second substrate 301 of the differentsubstrate, and electrode 352 and wirings 354 and external connectionpads 356 are formed, for connecting to circuit devices of circuit/deviceforming region 102 a of single crystal Si (111) thin-film device 112.

As an alternative configuration, an integrated device may be configuredsuch that plural devices having different functions are formed on secondsubstrate 301 and are electrically or optically connected tocircuit/device forming region 102. Alternatively, an integrated devicemay be configured such that multiple single crystal Si (111) thin-filmdevices 112 are bonded to each other and bonded to the surface of secondsubstrate 301.

FIG. 5 is a flowchart illustrating a method for manufacturing asemiconductor device in the first embodiment of the invention. The mainmanufacturing process includes steps of: forming an isolated islandincluding a circuit/device forming region on a surface of an Si (111)substrate (step S1); forming a coating layer that coats the surface ofthe isolated island (step S2); etching an exposed area of the surface ofSi (111) substrate along the (111) plane and separating the isolatedisland from the Si (111) substrate (step S3); and bonding the separatedsurface of the separated isolated island to a surface of a differentsubstrate (step S4).

In addition, bonded single crystal Si (111) thin-film device 112 caninclude circuit elements made of Si. Such circuit elements may include ap-n junction structure, a MOS structure, a structure such as acapacitor/resistor/coil or the like, or an electrode/wiring structure orthe like. In addition, single crystal Si (111) thin-film device 112 caninclude an electric/electronic device such as a sensor device, a solarcell device, a high-frequency device or the like, which is made of Si,an optical device such as a waveguide, a reflecting mirror or the like,a composite element thereof, or the like. Furthermore, single crystal Si(111) thin-film device 112 may include an antenna device, apiezoelectric device, a light emitting device or the like on the upperpart of the Si thin film. Single crystal Si (111) thin-film device 112may also include a material other than Si on the Si layer, for example,a heterogeneous semiconductor material layer such as SiGe, a compoundsemiconductor or the like.

In addition, in the embodiment, since separated single crystal Si (111)thin-film device 112 can be bonded to the heterogeneous materialsubstrate as described above, the Si device having a structure similarto a device using an existing SOI substrate or an SOS (Silicon onSapphire) substrate can be implemented.

In contrast, since material of a SOI substrate or a SOS substrate ismore expensive than the Si substrate and a SOI substrate or a SOSsubstrate is scribed in manufacturing devices in the substrate, it isnot possible to reuse the SOI substrate or the SOI substrate.

The first embodiment may be summarized by the following list.

(1) The first embodiment includes: the step of separating the isolatedisland including the circuit/device forming region, which is an upperlayer of the Si (111) substrate, by anisotropic etching along the (111)plane; and the step of bonding the separated single crystal Si (111)thin-film device to the surface of the second substrate of the differentsubstrate. Thus, there is no need to provide a sacrificial layer forexecuting selective etching during the separating step, and a singlecrystal (Si) thin film can be obtained by using inexpensive substrateswith a large diameter. In addition, there is no need to remove the Si(111) substrate by etching, polishing or the like in a thicknessdirection during the separating step. Thus, a single crystal Si thinfilm can be obtained through the simple and inexpensive manufacturingprocess.

(2) The separated surface of the single crystal Si (111) thin-filmdevice has extremely high flatness and thus the distance between bondingsurfaces can be in the order of a nanometer. Thus, a number of bondingconfigurations can be used including not only intermolecular forcebonding but also bonding using a chemical binding such as covalentbinding or the like and bonding using an adhesive or the like.Accordingly, the bonding conditions can be eased.

(3) A thin-film device made of single crystal Si can be placed in directand close contact, bonded, and then fixed onto a different substrate ora bonding layer provided on the different substrate. Thus,high-quality/high-performance devices having different materials as basematerials or different functions can be integrated in high density,while maintaining quality and performance. In addition, as mobility of aSi (111) carrier is higher than Si (100), a high density andmulti-functional integrated device can be obtained which makes full useof the characteristic of faster operation. Additionally, in bonding thesingle crystal Si (111) thin-film device of the embodiment, there is noneed to add a flattening layer for bonding, and an extremely flatseparated surface can be directly bonded to a substrate with highthermal conductivity such as a metal substrate or the like and to abonding layer with high thermal conductivity such as a metal layer, anAIN layer, a diamond-like carbon layer or the like. Accordingly, it ispossible to provide excellent adhesion of a bonded interface, reduceheat resistance in the bonded interface and the bonding layer, and thusachieve high radiation performance of the single crystal Si (111)thin-film device.

(4) Furthermore, a structure in which the single crystal Si is firmlybonded onto the insulating film layer can be manufactured, and thussemiconductor devices having performance and functions comparable todevices using SOT substrates or SOS substrates which are manufactured bywafer bonding or the like can be manufactured at low cost.

(5) According to the manufacturing method of the embodiment, thethickness of the Si (111) substrate of the first substrate afterseparation of the isolated island does not widely vary from the initialthickness, and the Si (111) substrate remains in a state where thesurface thereof has favorable flatness. Hence, the Si (111) substratecan be reused, and saving of substrate materials can be achieved.

Modification

The first embodiment was described by using as an example theconfiguration in which a single crystal Si (111) thin-film deviceseparated from the Si (111) substrate is bonded to a differentsubstrate. However, it is possible to make the thickness of the singlecrystal Si (111) thin-film device to be separated from the Si (111)substrate a thickness that allows the single crystal Si (111) thin-filmdevice to standby itself and thereby obtain a self-standing Si piece (Sichip) after the separation from the Si (111) substrate. Being capable ofstanding by itself, the self-standing Si chip can be used as aself-standing and individual chip.

As in the first embodiment, the self-standing Si piece can include notonly various devices and components but also a circuit element made ofSi. That is to say, the self-standing Si piece can include a sensordevice, a solar cell device, an electric device, a high-frequency deviceor the like which are made of Si.

Furthermore, the self-standing Si piece can include an optical devicehaving a waveguide or reflecting mirror or the like, a composite devicethereof, or the like. Additionally, the self-standing Si piece mayinclude an antenna device, a piezoelectric device, a light emittingdevice or the like on the upper part of the isolated island.Alternatively, the self-standing Si piece may include a material otherthan Si, for example, a heterogeneous semiconductor material layer suchas SiGe, a compound semiconductor or the like.

Second Embodiment

A second embodiment of the invention is described with reference to FIG.6A and FIG. 6B. The second embodiment provides a semiconductor compositechip in which the single crystal Si (111) thin-film device described inthe first embodiment (hereinafter referred to as an Si (111) thin-filmintegrated device) and one-dimensionally arranged light emitting devices(hereinafter referred to as a single crystal compound semiconductor thinfilm) are bonded and integrated on a single substrate, the Si (111)thin-film integrated device including the circuit/device forming regionsseparated from the Si (111) substrate.

FIG. 6A is a plan view for illustrating semiconductor composite chip3010 of the embodiment. In semiconductor composite chip 3010 singlecrystal compound semiconductor thin film 1010 and Si (111) thin-filmintegrated device 1040 are bonded and integrated on a surface ofsubstrate 1001.

For example, substrate 1001 is a Si substrate. In addition, substrate1001 may be of a glass substrate, a ceramics substrate, a plasticsubstrate such as PET, PEN or the like, a metal substrate such asstainless, nickel, copper, brass, aluminum or the like, a plated metalsubstrate obtained by plating a metal substrate with nickel or copper,or the like.

Si (111) thin-film integrated device 1040 is an Si (111) thin-filmintegrated device which is separated from the Si (111) substrate,directly contacted, bonded, and fixed to substrate 1001 or to bondinglayer 1112 provided on a surface of substrate 1001. Si (111) thin-filmintegrated device 1040 includes a group of CMOS integrated circuits fordriving single crystal compound semiconductor thin film 1010, the CMOSintegrated circuits including, for example, a shift register circuit inthe circuit/device forming region. Si (111) thin-film integrated device1040 has preferably R_(PV)≦2 nm as flatness of the bonded surface(separated surface), more preferably R_(PV)≦1 nm. It is also preferablethat Si (111) thin-film integrated device 1040 is bonded to the surfaceof substrate 1001 by intermolecular bonding or bonding such as covalentbinding or the like.

Single crystal compound semiconductor thin film 1010 is a thin filmincluding an array of light emitting diodes, and is a single crystalcompound semiconductor thin film, for example. More specific examples ofmaterials include a single crystal semiconductor thin film formed of aGaAs layer including a p-n junction, and an AIGaAs layer. Single crystalcompound semiconductor thin film 1010 is in direct close-contact withsubstrate 1001 or bonding layer 1112 provided on substrate 1001, bondedby an intermolecular force (intermolecular force bonding) and fixedthereto.

In single crystal compound semiconductor thin film 1010, multiple lightemitting devices including light emitting regions 1020, first electrodes1022, second electrodes 1024, and third electrodes 1026 for controllinglight emission, respectively, are formed in an array. The light emittingdevices include a first p-n junction and a second p-n junction, andinclude first electrodes 1022 as an electrode of a first conductivetype, second electrodes 1024 as a first electrode of a second conductivetype, and third electrodes 1026 as a second electrode of the secondconductive type. For example, third electrodes 1026 are commonelectrodes for the array of the light emitting devices.

Second electrodes 1024 and third electrodes 1026 in single crystalcompound semiconductor thin film 1010 are respectively connected viathin-film wirings 1034 and thin-film wirings 1036 as wirings to Si (111)thin-film integrated device 1040. For example, Si (111) thin-filmintegrated device 1040 includes a circuit for controlling the ON stateof each of the light emitting devices for second electrode 1024terminals of single crystal compound semiconductor thin film 1010 viathin-film wirings 1034. Thin-film wirings 1034 and thin-film wirings1036 are formed of metal thin-film wirings. The thin-film wirings to Si(111) thin-film integrated device 1040 are each structured to extendover the side of Si (111) thin-film integrated device 1040.

Then, as a configuration of external input wirings of semiconductorcomposite chip 3010, common wirings 1030 for the first electrodes 1022are connected to first electrodes 1022 of multiple light emitting diodesof single crystal compound semiconductor thin film 1010, and firstcommon wirings 1030 are connected to first common wiring connection pads1032 on substrate 1001. In addition, provided as wirings to Si (111)thin-film integrated device 1040 on substrate 1001, connection pads 1050are external input wiring pads which are formed on Si (111) thin-filmintegrated device 1040 for supplying power and inputting signals to thegroup of CMOS integrated circuits including, for example, the shiftregister circuit.

Thus, semiconductor composite chip 3010 of the embodiment has thefollowing configuration. Single crystal compound semiconductor thin film1010 including the light emitting devices and Si (111) thin-filmintegrated device 1040 for driving the light emitting devices are indirect and close contact, bonded, and fixed on the separated surface, asa bonding surface, of substrate 1001 or on bonding layer 1112 providedon substrate 1001. Then, both are connected by the thin-film wirings.The light emitting devices, which are components of single crystalcompound semiconductor thin film 1010, each include the first p-njunction, the second p-n junction, and three electrodes of the firstelectrode 1022, second electrode 1024 and third electrode 1026. Si (111)thin-film integrated device 1040 includes a circuit for controllingcurrent flowing between first electrode 1022 and third electrode 1026 byusing second electrode 1024, and controlling the ON state of each of thelight emitting devices.

FIG. 6B is a cross sectional view showing a cross section ofsemiconductor composite chip 3010 taken along the A-A line of FIG. 6A.Note that, in FIG. 6B, the same reference numerals are given to commonelements shown in FIG. 6A.

On substrate 1001, metal layer 1110 is provided for the light emittingdevices. Metal layer 1110 serves as a reflective film (HR film) whichreflects light emitted from light emitting region 1020 of each of thelight emitting devices in a direction to substrate 1001 and reflects thelight to the surface side of the light emitting device, which is adisplay direction of the light emitting device. In addition, bondinglayer 112 is a bonding layer for intermolecular force bonding (fordirectly and closely contacting and bonding surfaces to be bonded, andfixing the surfaces on bonding layer 1112) to single crystal compoundsemiconductor thin film 1010, and is, for example, an insulating filmsuch as an SiO₂ film, an SiN film, an SiON film, an Al₂O₃ film, an AINfilm, a diamond-like carbon film or the like, or an organic film.

FIG. 6B shows the state in which Si (111) thin-film integrated device1040 is bonded on bonding layer 1112 (intermolecular force bonding, forexample). However, the bonding of single crystal compound semiconductorthin film 1010 including the light emitting devices and Si (111)thin-film integrated device 1040 may alternatively be configured asfollows. The separated surfaces of the semiconductor thin films ofsingle crystal compound semiconductor thin film 1010 and Si (111)thin-film integrated device 1040 may be in direct close-contact, bonded,and fixed to bonding layer 1112 by using the separated surfaces thereofas the bonding surfaces. In this case, intermolecular force bonding isemployed for the bonding. As another case, bonding using anintermolecular force (intermolecular bonding) acting on the bondingsurfaces may be employed for bonding single crystal compoundsemiconductor thin film 1010 including the light emitting devices, whilebonding using strong binding such as covalent binding or the like isemployed for bonding Si (111) thin-film integrated device 1040.

According to the second embodiment of the invention, the followingconfiguration can be implemented. Specifically, separated surfaces ofsingle crystal compound semiconductor thin film 1010 including the lightemitting devices and Si (111) thin-film integrated device 1040 are indirect and close contact, bonded and fixed on substrate 1001 or onbonding layer 1112 provided on substrate 1001, by using the separatedsurfaces thereof as the bonding surfaces. In addition, the lightemitting devices and the integrated device are connected by thethin-film wirings. Consequently, the light emitting devices and thedriving integrated device can be integrated on the substrate in higherdensity than the conventional configuration, and a highly reliablecomposite semiconductor device can be implemented in a compactconfiguration a and at low cost. Furthermore, in the configuration, thesingle crystal compound semiconductor thin film and the Si (111)thin-film integrated device are directly bonded to the substrate or thebonding layer provided on the substrate by using the separated surfaceshaving extremely favorable flatness as the bonding surfaces.Accordingly, a semiconductor device with high radiation performance canbe implemented by using a substrate with high thermal conductivity suchas a metal substrate and a bonding layer with high thermal conductivitysuch as a metal layer, an AIN layer, a diamond-like carbon layer or thelike.

Furthermore, the light emitting devices include the first p-n junctionand the second p-n junction, and the three electrodes of the first tothird electrodes. In addition, Si (111) thin-film integrated device 1040includes a circuit for controlling the ON state of each of the lightemitting devices via the second electrode of the light emitting device.Thus, the group of CMOS integrated circuits of Si (111) thin-filmintegrated device 1040 for controlling light emission of the lightemitting devices can be reduced in size. Accordingly, the effect ofintegrating the group of light emitting devices and the group of CMOSintegrated driving devices on a heterogeneous substrate in high densitycan be achieved.

Third Embodiment

In a third embodiment of the invention, with reference to FIG. 7 andFIG. 8, a description is given of a configuration of a one dimensionallight emitting device array light source in which multiple semiconductorcomposite chips are arranged one-dimensionally. Each of thesemiconductor composite chips includes single crystal compoundsemiconductor thin film 1010 and Si (111) thin-film integrated device1040 which are integrated therein, as described in the secondembodiment.

In FIG. 7, one-dimensional light emitting device array source 4000includes multiple semiconductor composite chips 3010 which are onedimensionally arranged on wiring substrate 3050, wiring regions 3020,3030, chip mount region 3040, and connection terminal 3060.

Wiring substrate 3050 is, for example, a glass epoxy substrate, a metalcore wiring substrate including a metal core, a glass substrate, aplastic substrate, a metal substrate, a ceramics substrate or the like.

Wiring regions 3020, 3030 are for supplying power and inputting acontrol signal to semiconductor composite chip 3010 mounted on substrate1001 via wirings provided in substrate 1001 from connection terminals toexternal circuits provided on substrate 1001, and a wiring region formaking connections with single crystal compound semiconductor thin film1010 and Si (111) thin-film integrated device 1040 which are integratedon the wiring and semiconductor composite chip 3010, respectively. Chipmount region 3040 includes an IC chip or the like for controlling theentire one-dimensional light emitting array light source 4000. Externalconnection terminal 3060 supplies power to control one-dimensional lightemitting device array light source 4000 and supplies a control signalfrom the external.

Semiconductor composite chip 3010 is the semiconductor composite chipdescribed in the second embodiment. The connection pads (common wiringconnection pad 1032 and connection pad 1050) described in the secondembodiment are respectively connected to wiring region 3020 and wiringregion 3030 on wiring substrate 3050 by a connection method such as wirebonding or the like.

FIG. 8 is a cross sectional view of LED print head 5000 which is anexample and on which one-dimensional light emitting array light source4000 is mounted. LED print head 5000 includes one-dimensional lightemitting device array light sources 4000, rod lens array 4020, and headframe 4010. In the embodiment, connection pads on semiconductorcomposite chip 3010 are respectively connected to wiring region 3020 andwiring region 3030 on wiring board 3050 by bonding wires 3070.

According to the third embodiment of the invention, the one-dimensionallight emitting device array light source 4000 is configured by using thecompact semiconductor composite chip on which single crystal compoundsemiconductor thin film 1010 and Si (111) thin-film integrated device 40are integrated. Thus, compact one-dimensional light emitting devicearray light source 4000 and compact LED print head 5000 can beimplemented.

Modification

A modification of the one-dimensional light emitting device array lightsource of the second embodiment and the third embodiment is describedwith reference to FIG. 9A and FIG. 9B. FIG. 9A is a plan view, whileFIG. 9B is a cross sectional view taken along the line B-B of FIG. 9A.

In FIG. 9A, one-dimensional light emitting device array light source4001 of the modification is configured such that multiple single crystalcompound semiconductor thin films 1010 and multiple Si (111) thin-filmintegrated devices 1040, which are described in the second embodiment,are arranged in rows and bonded on substrate 5050. In the bondingconfiguration, the separated surface of single crystal compoundsemiconductor thin film 1010 and Si (111) thin-film integrated device1040 are in direct and close contact, bonded, and fixed on bonding layer5112 provided on substrate 5050 by using the separated surfaces thereofas the bonding surfaces. That is to say, the configuration is such thatthe separated surfaces of single crystal compound semiconductor thinfilm 1010 and Si (111) thin-film integrated device 1040 are bonded onsubstrate 5050 or on bonding layer 5112 provided on substrate 5050 byusing the separated surfaces thereof as the bonding surfaces, byintermolecular force bonding or bonding using a strong binding such ascovalent binding or the like. In addition, connection is established bythin-film wirings 5070 between single crystal compound semiconductorthin film 1010 and Si (111) thin-film integrated device 1040, betweensingle crystal compound semiconductor thin film 1010 and wiring region5020, and between Si (111) thin-film integrated device 1040 and wiringregion 5030. Furthermore, chip mount 3040 and external connectionterminal 3060 are provided as in the fourth embodiment.

In addition, substrate 5050 is a glass substrate, a ceramics substrate,a plastic substrate such as PET or PEN or the like, a metal substratesuch as stainless steel, nickel, copper, brass, aluminum or the like, aplated metal substrate obtained by plating a metal substrate with nickelor copper, or the like. The description of the other components isfinished in the second and third embodiments, and thus is omittedherein.

In addition, a configuration of the modification is described withreference to the cross sectional view shown in FIG. 9B. With theconfiguration in which multiple single crystal compound semiconductorthin films 1010 and multiple Si (111) thin-film integrated devices 1040are arranged in rows and are bonded on the surface of bonding layer 5112of single substrate 5050, thin-film wirings 5070 can connect betweensingle crystal compound semiconductor thin film 1010 and Si (111)thin-film integrated device 1040, between single crystal compoundsemiconductor thin film 1010 and wiring region 5020, and between Si(111) thin-film integrated device 1040 and wiring region 5030,respectively. Accordingly, the connection by wire bonding described inthe third embodiment can be omitted.

With the modification, mounting density can be increased more thanone-dimensional light emitting device array light source 4000 of thethird embodiment, and reduction in size can be achieved.

Fourth Embodiment

A fourth embodiment of the invention is described with reference to FIG.10 to FIG. 13. In the embodiment, multiple single crystal compoundsemiconductor thin films and two Si (111) thin-film integrated devicesare bonded on a single substrate, the single crystal compoundsemiconductor thin films being arranged two-dimensionally, the Si (111)thin-film integrated devices being provided for driving 3-terminal lightemitting devices included in each of the multiple single crystalcompound semiconductor thin films which are two-dimensionally arranged.

FIG. 10 is a plan view for illustrating the fourth embodiment of theinvention.

In FIG. 10, metal conductive layer 7002 is provided on substrate 7001,and multiple single crystal compound semiconductor thin films 7010 aretwo-dimensionally arranged and bonded on metal conductive layer 7002with connection layer 7004 interposed in between. In addition, twoSi(111) thin-film integrated devices are arranged and bonded onsubstrate 7001 with connection layer 7004 interposed in between, the twoSi (111) thin-film integrated devices being first Si (111) thin-filmintegrated device 7110 and second Si (111) thin-film integrated device7210.

Substrate 7001 is, for example, a glass substrate, a ceramics substrate,a plastic substrate such as PET or PEN or the like, a metal substratesuch as stainless, nickel, copper, brass, aluminum or the like, a platedmetal substrate obtained by plating a metal substrate with nickel orcopper, or the like.

Metal conductive layer 7002 causes third electrode 7026 of singlecrystal compound semiconductor thin film 7010 provided on substrate 7001to serve as a common electrode, and provides the common electrode with acommon potential (ground potential). Then, connection wiring 7510connects common electrode 7026 (FIG. 11) of the light emitting devicewith metal conductive layer 7002.

Each of single crystal compound semiconductor thin film 7010 includes agroup of 3-terminal light emitting devices each having a first p-njunction, a second p-n junction, light emitting region 7012, firstelectrode 7022, second electrode 7024, and third electrode 7026.

First Si (111) thin-film integrated device 7110 is a Si (111) thin-filmintegrated device for controlling second electrode 7024 of the lightemitting device to control the ON state of the light emitting device,and is a Si (111) thin-film integrated circuit device, for example,including a shift register circuit. In addition, second Si (111)thin-film integrated device 7210 controls first electrode 7022 of thelight emitting device to control the ON state of the light emittingdevice, and is a Si (111) thin-film integrated device, for example,including a shift register circuit, an IC for controlling electriccurrent, or the like.

External connection wiring 7540 is a connection wiring on substrate7010, which connects a terminal (not shown) for connecting metalconductive layer 7002 and the external of substrate 7001. FIG. 11, FIG.12 and FIG. 13 respectively show a cross sectional view taken along theline A-A of FIG. 10, a cross sectional view taken along the line B-B,and a cross sectional view taken along the line C-C. In addition, thesame reference numerals as those in FIG. 10 are given to the samecomponents.

According to the fourth embodiment of the invention, the two-dimensionalarray of the light emitting devices which are multiple two-dimensionallyarranged single crystal compound semiconductor thin films and two Si(111) thin-film integrated devices for driving the light emittingdevices are bonded and integrated on the same substrate. Accordingly,connection among the light emitting devices and the driving circuits canbe established by thin-film wirings, and thus a compact two-dimensionallight emitting array integrated with the driving circuits can beachieved.

Here, the multiple single crystal compound semiconductor thin films andthe Si (111) thin-film integrated devices are bonded on the substrate inthe following manner. The separated surfaces of the single crystalcompound semiconductor thin films and the Si (111) thin-film integrateddevices are in direct and close contact, bonded, and fixed on substrate7001 or on the bonding layer provided on substrate 7001 by using theseparated surfaces thereof as the bonding surfaces. That is to say, theseparated surfaces of the single crystal compound semiconductor thinfilms and the Si (iii)) thin-film integrated devices are bonded onsubstrate 7001 or on the bonding layer provided on substrate 7001, byusing the separated surfaces thereof as the bonding surfaces, byintermolecular force bonding or bonding using a strong binding such ascovalent binding or the like.

Modification

A modification of the embodiment is described with reference to FIG. 14.In the fourth embodiment, the light emitting devices are 3-terminallight emitting devices each including a first p-n junction, a second p-njunction, and first to third electrodes. However, the modification showsa configuration of 2-terminal light emitting devices as single crystalcompound semiconductor thin film 8010, each including a p-n junction,first electrode 8022 and second electrode 8024. The configuration can besuch that first Si (111) thin-film integrated device 8110 and second Si(111) thin-film integrated device 8210 are bonded, both including ashift register circuit and an IC for controlling current, as a drivingcircuit for driving the light emitting devices.

Here, first Si (111) thin-film integrated device 8110 and secondthin-film integrated device 8210 are bonded on the substrate in thefollowing manner. Separated surfaces of first Si (111) thin-filmintegrated device 8110 and second Si (111) thin-film integrated device8210 are in direct and close contact, bonded, and fixed on substrate8001 or the bonding layer provided on substrate 8001, by using theseparated surfaces thereof as the bonding surfaces. That is to say, inthe configuration, first Si (111) thin-film integrated device 8110 andsecond Si (111) thin-film integrated device 8210 are bonded on substrate8001 or on the bonding layer provided on substrate 8001 by using theseparated surfaces thereof as the bonding surfaces by intermolecularforce bonding or bonding using a strong binding such as covalentbinding.

In addition, in the embodiment, although the description is given bytaking the light emitting devices of the single crystal thin film as anexample, light emitting devices using an organic material may be usedinstead of the light emitting devices of the single crystal thin film.

What is claimed is:
 1. A semiconductor device comprising: a substratehaving a surface; a light emitting element having an electrode formingsurface and a bonding surface provided on an opposite side to theelectrode forming surface, the bonding surface directly bonded to thesurface of the substrate; and a Si (111) element having a first surfaceand a second surface opposed to the first surface, the Si (111) elementincluding an integrated circuit configured to drive the light emittingelement, wherein the second surface of the Si (111) element is directlybonded to the surface of the substrate; the light emitting elementincludes a first electrode, a second electrode and a third electrode,the second electrode is connected to the integrated circuit by a metalthin-film wiring, wherein the integrated circuit of the Si (111) elementcomprises a controller configured to control an electrical currentflowing between the first electrode and the third electrode.
 2. Asemiconductor device according to claim 1, wherein the second surface ofthe Si (111) element is bonded to the surface of the substrate byintermolecular force.
 3. A semiconductor device according to claim 1,wherein the surface of the substrate has a bonding layer, and the secondsurface of the Si (111) element is directly bonded to the bonding layer.4. A semiconductor device according to claim 3, wherein the secondsurface of the Si (111) element is bonded to the bonding layer byintermolecular force.
 5. A semiconductor device according to claim 1,wherein the bonding surface of the light emitting element is bonded tothe surface of the substrate by intermolecular force.
 6. A semiconductordevice according to claim 1, wherein the surface of the substrateincludes a bonding layer, and the bonding surface of the light emittingelement is directly bonded to the bonding layer.
 7. A semiconductordevice according to claim 6, wherein the bonding surface of the lightemitting element is bonded to the bonding layer by intermolecular force.8. A semiconductor device according to claim 1, wherein the lightemitting element is made of a compound semiconductor.
 9. A semiconductordevice according to claim 1, wherein the light emitting element includesat least a first PN junction and a second PN junction.
 10. Asemiconductor device according to claim 1, wherein the substrate is ametal substrate.
 11. A semiconductor device according to claim 2,wherein a flatness of the second surface of the Si (111) element isequal to or less than 2 nm.
 12. A semiconductor device according toclaim 3, wherein the bonding layer is a metal layer, an AIN layer, or adiamond-like carbon layer.
 13. A semiconductor device according to claim6, wherein the bonding layer is a metal layer, an AIN layer, or adiamond-like carbon layer.
 14. A semiconductor device according to claim1, wherein the Si (111) element includes at least one of an antennadevice, piezoelectric device on the first surface of the Si (111)element.
 15. A semiconductor device according to claim 1, wherein the Si(111) element includes at least one of a solar cell device, ahigh-frequency device, an optical device, and a reflecting mirror.